taqumi design

design portfolio of Takumi Yoshida

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Aptus | Skin & Bone Pen
Unique and stylish pen design as a result of pursuit of essentialism in writing instruments.

“Aptus” is a latin word for suitable, appropriate or fitting. The main concept behind the design is essentialism. It is designed for relatively young to mid aged men and women who would not hesitate to challenge old conventions and pay strict attentions to the details of their lifestyle as a whole.

Its unique and elegant form is a result of pursuing pure essentialism of a pen and it combines such appearance with practical functionality and ergonomics.

Just to address some misunderstanding I noticed in feedbacks on the web, the straight shaft penetrating the frame in the middle is NOT the refill pen. It is a very thin hollow shaft accommodating the actual ‘bare’ pen insde.



Bone and Skin

A. The volume required for a pen itself, purely in terms of its mechanical requirements, can be very thin. While all existing pens accommodate for ergonomics by simply increasing the volume of the housing, Aptus instead seperates volume required for the mechanism and ergonomics and pursued both elements respectively
to the extreme.

B. As shown in the diagram above despite its bodyless appearance, Aptus provides large four contact points (three points near the tip of the pen and one supporting point between the thumb and the index finger) when held in a hand so that it gives a same holding and writing experience if not better.

Prototype Development

Casted brass frame

The main frame (the Skin) is made from cast brass using ivestment casting method.

  • Top left: Initial RP models to be invested for making mould
  • Top right: First model of a casted brass part. The rough surface finish of RP is apparent.
  • Right: sanded brass part with a central shaft inserted.

Frame with central shaft inserted